Ana turns 30 on New Year's Day, with her life still unresolved: she lives in a shared apartment, dislikes her job, and frequently changes friends. Óscar turns 30 on New Year's Eve, with his life almost figured out: a passionate doctor, loyal friends, and a relationship that comes and goes. Just as they both reach their thirties, they meet, fall in love, and begin a relationship that will last ten years. The story is told in 10 episodes, all revolving around the same moment of the year: New Year's Eves.